Rapidly absorbed (immediate)25-30% bioavailabilitySmokingThe effects associated with smoking are widely debated, and there is lung irritation and carcinogens produced from combustion. Health professionals are in agreement that smoke-free methods pose less risk and are medically preferred. VaporizingVaporizing allows cannabinoids to rapidly enter the bloodstream. A vaporizer steadily heats herbs to a temperature that is high enough to extract THC, CBD, and other cannabinoids but too low for the potentially harmful toxins that are released during combustion; essentially, vaporization eliminates the health risks associated with smoking. Vaporizing has a reduction in odor, also.

Quickly absorbed (15-20 minutes) 15-30% bioavailabilityNasalspraysA relatively new method of administering cannabis, nasal sprays allow rapid absorption. This is helpful for patients with extreme nausea or who may be unconscious. TincturesGenerally, drops of the tincture are placed under the tongue, where it’s absorbed into the body versus swallowed and digested. Oral-mucosal absorption is rapid. bypassing the gastrointestinal tract and first-pass metabolism in the liver.Quickly absorbed (15-20 minutes)60-70% bioavailabilitySuppositoriesRectal suppositories are helpful if the oral route is impaired due to injury, nausea, or GI difficulties. Suppositories are absorbed into the bloodstream which results in superior bioavailability. This prevents first-pass metabolism by the stomach and liver, which break down many different molecules into their constituent parts (including Δ9-tetrahydrocannabinol, otherwise known as THC)Slowly absorbed (1-2 hours)10-20% bioavailabilityOilsOil is consumed orally is more potent in the bloodstream, and it has a longer half-life, thus providing relief longer for such conditions as inflammation, spasticity, seizure control Oil can be produced in various methods. One method is mixing cannabis with alcohol and then evaporating the solvent, leaving behind a tar-like substance resembling oil. CO2 extraction is a clean method of extracting oil that currently involves expensive equipment. A home-made method is infusing plant material with oil, heating, then straining the oil. EdiblesLozenges and food can be infused with cannabis for a slower release. Also cannabis flower can be baked and incorporated into capsules, etc. States such as New Jersey specify edibles for children. Teas are specifically indicated for nausea or appetite stimulation. Juicing raw cannabis is a way to obtain cannabinoids without the psychoactive effects of THC.Slowly absorbed (1-2 hours)Local absorptionTopicalsTopical cannabis is a thick oil that has been decarboxylated to activate cannabinoids. It can be made into creams or a patch for absorption into the skin. Topical administration is said to provide relief from pain without the cerebral stimulation that users describe as "being high."